JP2011247183A - Scroll type fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll type fluid machine in which stress concentrations generated in fixed and movable spiral bodies are suppressed, the airtightness of a compression chamber or an expansion chamber of a working fluid formed between the spiral bodies is enhanced, and which has enhanced working efficiency and is compact in size.SOLUTION: The scroll type fluid machine is provided in which spiral bodies 50, 52 and an end plate 10a are brought into slide-contact with each other in a space between fixed and moving scrolls 8, 10 by means of a tip seal 56 provided on the spiral bodies to thereby partition a working fluid pressure chamber between the spiral bodies. The spiral body of at least one scroll has a base 62 comprising concave curved surfaces 64 at the base plate side edge of the spiral body, and the tip seal of the other scroll has fillets 70 comprising first convex curved surfaces 72 which are brought in slide-contact with the concave curved surfaces at the corner the tip 56a of the tip seal.

Description

  The present invention relates to a scroll type fluid machine suitable for a refrigeration circuit used for air conditioning of a vehicle.

This type of scroll-type fluid machine includes a fixed scroll and a movable scroll each having an end plate and a spiral body integral with the end plate, and the spiral body and the end plate are in sliding contact with each other between the fixed and movable scrolls. A compression chamber or expansion chamber for the working fluid formed between the spiral bodies is defined.
In Patent Document 1, a root portion of the radius of curvature (r) is provided at the corner on the end plate side of the scroll body of one scroll, and the radius of curvature (R) is provided at the corner of the tip of the spiral body of the other scroll. A scroll compressor is disclosed in which a rounded portion is provided and the radius of curvature (R) is larger than the radius of curvature (r).

In Patent Document 2, an arc-shaped first chamfered portion is provided at the base of the spiral body, and an arc-shaped second chamfered portion slightly smaller than the first chamfered portion is provided at the corner of the tip of the spiral body. A scroll compressor is disclosed in which the radius of the first and second chamfered portions is 5% or less of the thickness of the spiral body.
Further, Patent Document 3 discloses a scroll compressor in which a gap portion of a compression chamber is formed on at least one surface of both scrolls and is filled with a surface treatment material having a lower hardness than the other scroll. Yes.

Furthermore, Patent Document 4 discloses a scroll type fluid machine in which an interference escape portion with a base portion of a spiral body is formed on a second end plate (bottom plate).
Further, in Patent Document 5, the spiral body and the end plate are in sliding contact with each other through a chip seal provided on the spiral body between the fixed and movable scrolls, and the cross-sectional shape is made concave or convex at the tip of the spiral body. A scroll type fluid machine equipped with a tip seal is disclosed.

Japanese Patent No. 4126815 JP-A-5-187371 JP 2001-342979 A Japanese Unexamined Patent Publication No. 57-148085 JP 2000-352388 A

By the way, in recent years, the weight reduction of the vehicle has been promoted by the increase in environmental awareness, and the engine room tends to be narrowed to improve the comfort of the vehicle cabin. For example, a small scroll type that can be installed in a narrow engine room There is a need for fluid machinery.
However, the scroll unit of the scroll type fluid machine generally has a cantilever structure in which the movable scroll pivots with respect to the fixed scroll. In order to secure the discharge capacity while reducing the size of the scroll unit, the scroll body is formed high. Therefore, the spiral body is easily damaged. Therefore, to prevent damage to the spiral body, the spiral body must be formed of an expensive high-strength material. If this is not possible, the height of the spiral body must be reduced, resulting in a smaller fluid machine. There were restrictions on promotion.

In this way, in order to promote the downsizing of the fluid machine by raising the spiral body without forming the spiral body from a high-strength material, the stress concentration generated in the spiral body due to the orbiting movement of the movable scroll is suppressed and the spiral body is suppressed. It is necessary to prevent damage.
Therefore, in Patent Documents 1 and 2, arc-shaped so-called fillet portions are formed at the root portion and the tip portion of the spiral body, but their curvature radii are different from each other. Further, since these fillet portions are formed in the spiral body itself, there is a possibility that the fillet portions may be worn with the turning motion of the movable scroll. Therefore, it is inevitable that a gap of a three-month cross section is generated between the root portion and the tip portion between the fixed and movable spiral bodies, and the airtightness of the compression chamber or the expansion chamber cannot be secured, and as a result The operating efficiency of the machine may be significantly reduced.

Further, as described in Patent Document 2, when the radius of curvature of the fillet portion is set to 5% or less of the wall thickness of the spiral body, especially in the case of a small fluid machine, the fillet portion is too small. It is difficult to reliably fill the monthly gap, and stress concentration generated in the spiral body may not be sufficiently suppressed.
On the other hand, in Patent Document 3, it is considered that the surface treatment material is worn to an appropriate film thickness by filling the fillet part with a surface treatment material, for example, soft metal plating, so that the three-month gap can be filled. However, in the first place, the surface treatment material is generally formed with a thickness of the order of micron and wear is not assumed, and since the surface treatment material that is too thick may peel off, it is difficult to fill the three-month gap. In addition, there is a possibility that the stress concentration generated in the spiral body cannot be sufficiently suppressed.

Moreover, in the said patent document 4, a clearance gap may arise between the root part of a spiral body and a bottom plate besides the said 3 months-like clearance gap, and the airtightness of a compression chamber or an expansion chamber cannot be ensured.
Therefore, as described in Patent Document 5, it seems that the three-month gap can be filled with a chip seal by attaching a concave or convex chip seal to the tip of the spiral body. No special consideration has been given to the corner shape of the seal tip or the tip seal deformation caused by the orbiting movement of the orbiting scroll. Therefore, the three-month gap is surely filled, and the stress concentration generated in the spiral body is reduced. There are still issues to be addressed.

  The present invention has been made based on the above-described circumstances, and an object of the present invention is to suppress the stress concentration generated in the fixed and movable spiral bodies, and to compress or expand the working fluid formed between the spiral bodies. It is an object of the present invention to provide a scroll type fluid machine that can be reduced in size while improving airtightness and improving operating efficiency.

  In order to achieve the above object, a scroll type fluid machine according to the present invention includes a fixed scroll and a movable scroll each having an end plate and a spiral body integral with the end plate. A scroll type fluid machine that partitions a pressure chamber of a working fluid formed between the spiral bodies by sliding the end plates in contact with each other via a tip seal provided on the spiral body, and the spiral body of at least one scroll is The tip seal of the other scroll has a fillet portion formed of a first convex arc surface that is in sliding contact with the concave arc surface at the corner of the tip. (Claim 1).

More specifically, the chip seal has a locking portion locked to the spiral body, and the locking portion is provided on the inner side in the width direction of the chip seal than the fillet portion (Claim 2).
Preferably, when the width of the spiral body is W1 and the width of the tip seal is W2, the relationship represented by W2> W1 is satisfied.
Preferably, the tip seal has a second convex arc surface covering the central end of the spiral body, and when the radius of curvature of the first convex arc surface is R1, and the radius of curvature of the second convex arc surface is R2, R2 The relationship represented by> R1 is satisfied (claim 4).

Preferably, when the radius of curvature of the concave arc surface is R0 and the radius of curvature of the first convex arc surface is R1, the relationship represented by (R0−0.1 mm) ≦ R1 ≦ (R0 + 0.1 mm) is satisfied ( Claim 5).
Preferably, the first convex arc surface of the fillet portion is provided with an auxiliary rib for assisting the seal with the concave arc surface with the third convex arc surface, and the radius of curvature of the concave arc surface is R0. When the radius of curvature of the convex arc surface is R1 and the radius of curvature of the third convex arc surface is R3, the relationship represented by R3 ≦ R0 ≦ R1 is satisfied (claim 6).

  Preferably, the plurality of auxiliary ribs are densely provided closer to the center end of the spiral body (Claim 7).

  According to the scroll type fluid machine of the first aspect, since the tip seal has the fillet portion formed of the first convex arc surface at the corner of the tip portion, the tip seal is generated at the corner of the tip portion of the fixed and movable spiral body. Stress concentration can be suppressed. In addition, since the fillet portion formed by the first convex arc surface of the tip seal of the other scroll is in sliding contact with the root portion formed by the concave arc surface of the scroll body of one scroll, it is formed between the spiral bodies. Thus, the air tightness of the compression chamber or the expansion chamber of the working fluid can be improved, and the operation efficiency of the fluid machine can be improved, and the size can be reduced.

  According to the second aspect of the present invention, the tip seal has a locking portion locked to the spiral body, and the locking portion is provided on the inner side in the width direction of the chip seal than the fillet portion, and the fillet portion with respect to the root portion A slight deformation of the fillet portion is allowed with the sliding contact. Therefore, when the fillet portion is pressed against the root portion, the sealing performance between the spiral bodies and the airtightness of the pressure chamber can be further improved, and the operating efficiency of the fluid machine can be further improved.

  According to the third aspect of the present invention, when the width of the spiral body is W1 and the width of the tip seal is W2, the relationship represented by W2> W1 is satisfied. In addition, the fillet portion can be reliably pressed against the root portion, and the sealing performance between the spiral bodies and thus the airtightness of the pressure chamber can be further improved. Further improvement can be achieved.

  According to the fourth aspect of the present invention, the tip seal has the second convex arc surface covering the central end of the spiral body, the radius of curvature of the first convex arc surface is R1, and the radius of curvature of the second convex arc surface is When R2 is R2, since the relationship represented by R2> R1 is satisfied, the tip seal can be formed with a smooth curved surface continuous at the central end of the spiral body, and the sealing performance between the spiral bodies, and thus the pressure Since the airtightness of the chamber can be further increased, the operating efficiency of the fluid machine can be further improved.

  According to the fifth aspect of the present invention, when the radius of curvature of the concave arc surface is R0 and the radius of curvature of the first convex arc surface is R1, (R0−0.1 mm) ≦ R1 ≦ (R0 + 0.1 mm) Since the relationship shown is satisfied, the radius of curvature of the concave arc surface and the first convex arc surface can be set within an appropriate range taking into account the elastic deformation of the tip seal, and the sealing performance between the spiral bodies and thus the airtightness of the pressure chamber Therefore, the operating efficiency of the fluid machine can be further improved.

  According to the invention described in claim 6, the first convex arc surface of the fillet portion is provided with the auxiliary rib for assisting the seal with the concave arc surface with the third convex arc surface, and the curvature of the concave arc surface is provided. When the radius is R0, the radius of curvature of the first convex arc surface is R1, and the radius of curvature of the third convex arc surface is R3, the relationship expressed by R3 ≦ R0 ≦ R1 is satisfied. The radius of curvature of the concave arc surface and the first convex arc surface can be set within the range that has been taken into account, and the sealing performance between the spiral bodies and, in turn, the airtightness of the pressure chamber can be further enhanced, further improving the operating efficiency of the fluid machine. Can be improved.

  According to the seventh aspect of the present invention, since the plurality of auxiliary ribs are provided more densely toward the central end of the spiral body, the auxiliary ribs are provided in the vicinity of the central end of the spiral body where the pressure in the pressure chamber becomes the highest. Since the radius of curvature of the concave arc surface and the first convex arc surface can be set in a range that takes into account the wear of the cylinder, the sealing performance between the spiral bodies and the airtightness of the pressure chamber can be further effectively improved. The operating efficiency of the machine can be further improved.

It is sectional drawing which showed the scroll compressor which concerns on this invention. It is sectional drawing which showed the root part of the movable spiral body which concerns on 1st Embodiment of this invention, a fixed chip seal, and the front-end | tip part of a fixed spiral body. It is sectional drawing which looked at the fixed spiral body of FIG. 2 from the III-III direction. It is sectional drawing which showed the root part of the movable spiral body which concerns on 2nd Embodiment of this invention. It is sectional drawing which showed the fixed chip | tip seal | sticker which concerns on 2nd Embodiment of this invention. It is sectional drawing which showed the front-end | tip part of the fixed spiral body which concerns on 2nd Embodiment of this invention. It is sectional drawing which showed the state which a root part and a fillet part space apart and oppose at the time of the assembly | attachment of the movable scroll with respect to the fixed scroll which concerns on 2nd Embodiment of this invention. It is sectional drawing which showed the state which the side surface of a movable spiral body contact | abuts to the side surface of a fixed spiral body at the time of the assembly | attachment of the movable scroll with respect to the fixed scroll which concerns on 2nd Embodiment of this invention. It is principal part sectional drawing which showed the time of the turning motion of the movable scroll which concerns on 2nd Embodiment of this invention. It is sectional drawing which showed the fixed chip | tip seal | sticker which concerns on 3rd Embodiment of this invention. It is principal part sectional drawing which showed the time of the turning motion of the movable scroll which concerns on 3rd Embodiment of this invention. It is sectional drawing which looked at the fixed spiral body of FIG. 11 from the XII-XII direction. It is principal part sectional drawing which showed the time of the turning motion of the movable scroll which concerns on the modification of this invention. It is the top view which showed the movable scroll which concerns on another modification of this invention. It is sectional drawing which looked at the movable scroll of FIG. 14 from the VV direction.

FIG. 1 shows a scroll compressor (scroll type fluid machine) 1 according to the present invention. This compressor 1 is incorporated in a refrigeration circuit for air-conditioning a vehicle and compresses refrigerant (working fluid) circulating in the refrigeration circuit. used.
The compressor 1 includes a rear housing 2 and a front housing 4, and a scroll unit 6 is accommodated in the rear housing 2. The scroll unit 6 includes a fixed scroll 8 fixed to the rear housing 2 and a movable scroll 10 assembled so as to mesh with the fixed scroll 8. A series of processes from suction to compression to discharge are continuously performed.

  More specifically, a discharge chamber 12 is formed in the rear housing 2 between its end plate and the fixed scroll 8 of the scroll unit 6, and this discharge chamber 12 is a discharge hole formed in the end plate 8 a of the fixed scroll 8. 14 is connectable to the refrigerant circulation path of the refrigeration circuit via a discharge port (not shown) formed in the rear housing 2.

The rear housing 2 is also provided with a refrigerant suction port (not shown). The suction port introduces the refrigerant into the rear housing 2 from the refrigerant circulation path, and the introduced refrigerant enters the scroll unit 6. Inhaled.
On the other hand, a drive shaft 18 is disposed in the front housing 4, and the drive shaft 18 has a large-diameter end portion 20 and a small-diameter shaft portion 22. The large diameter end portion 20 is rotatably supported by the front housing 4 via a needle bearing 24, and the small diameter shaft portion 22 is rotatably supported by the front housing 4 via a ball bearing 26. Further, a lip seal 28 is disposed between the small diameter shaft portion 22 and the front housing 4, and the lip seal 28 partitions the front housing 4 in an airtight manner.

  A small-diameter shaft portion 22 of the drive shaft 18 protrudes from the front housing 4, and the protruding end is connected to a drive pulley 30 incorporating an electromagnetic clutch. The drive pulley 30 is rotatably supported by the front housing 4 via a bearing 32. ing. The driving pulley 30 is connected to an output pulley on the engine side of the vehicle via a belt, and is rotated by receiving power from the engine. Therefore, during driving of the engine, if the electromagnetic clutch in the drive pulley 30 is on, the drive shaft 18 rotates with the drive pulley 30.

  On the other hand, a crank pin 34 protrudes from the large-diameter end 20 of the drive shaft 18 toward the movable scroll 10, and the crank pin 34 supports the boss 40 of the movable scroll 10 via an eccentric bush 36 and a needle bearing 38. ing. Therefore, when the drive shaft 18 is rotated, the movable scroll 10 performs a turning motion via the crank pin 34 and the eccentric bush 36.

  Further, a rotation prevention coupling is disposed between the front housing 4 and the end plate 10 a of the movable scroll 10. In the case of this embodiment, the rotation prevention coupling comprises a so-called EM coupling 42, and the EM coupling 42 is configured by sandwiching a ball 48 between the annular race grooves of both the movable plate 44 and the fixed plate 46 each having a ring shape. ing.

The fixed scroll 8 has a fixed spiral 50 integrally formed with the end plate 8a, and the movable scroll 10 also has a movable spiral 52 integrally formed with the end plate 10a. The inner and outer surfaces of the fixed and movable spiral bodies 50 and 52 are formed of an involute curved surface except for the central end portion, and are formed of an aluminum alloy such as A4032-T6.
The discharge hole 14 described above is positioned in the vicinity of the central end portion 54 of the fixed spiral body 50, and a certain clearance is secured between the inner surface of the central end portion 54.

  A fixed tip seal 56 is provided at the tip 50 a of the fixed spiral body 50, and a movable tip seal 58 is provided at the tip 52 a of the movable spiral body 52. The fixed and movable tip seals 56 and 58 have an elastic coefficient of about 1/30 or less of that of the fixed and movable spiral bodies 50 and 52 formed from the aluminum alloy as described above, for example, engineering such as polyphenylene sulfide (PPS).・ Molded from plastic.

  The fixed spiral body 50 and the end plate 10 a are slidably contacted with each other via a fixed tip seal 56, while the movable spiral body 52 and the end plate 8 a are slidably contacted with each other via a movable tip seal 58. Due to the sliding contact between the fixed and movable scrolls 8 and 10, a refrigerant compression chamber (pressure chamber) 60 is defined between the fixed and movable spiral bodies 50 and 52, and the above-described series of processes continues. Executed.

  Hereinafter, with reference to the time of assembly of the movable scroll 10 with respect to the fixed scroll 8 in FIG. 2, the shapes of the root portion 62 of the movable spiral body 52, the fixed tip seal 56, and the distal end portion 50 a of the fixed spiral body 50 of the first embodiment will be described. This will be described in detail. In addition, since the root part of the fixed spiral body 50, the movable tip seal 58, and the tip end part 52a of the movable spiral body 52 have the same shape, description thereof will be omitted and fixed in all embodiments described later. The spiral body 50 may be simply referred to as the spiral body 50, and the fixed chip seal 56 may be simply referred to as the chip seal 56.

The movable spiral body 52 is formed to have a width W1, and has a root portion 62 at a corner on the end plate 10a side. The root portion 62 is formed to have a concave arc surface 64 with a radius of curvature R0 by a cutting tool such as an end mill at the stage of cutting the movable spiral body 52.
The fixed tip seal 56 has substantially the same length as that of the fixed spiral body 50 in the spiral direction, and is formed in a concave cross section in the present embodiment. On the other hand, the fixed spiral body 50 is formed in a convex shape in cross section, and a convex portion 66 is formed at the tip 50 a of the fixed spiral body 50. A fixed chip seal 56 is fixed to the fixed spiral body by fitting a concave portion (locking portion) 68 that forms a concave shape in cross section of the fixed chip seal 56 into the convex portion 66 of the fixed spiral body 50 along the spiral direction of the fixed spiral body 50. 50 is locked and attached.

The fixed chip seal 56 has fillet portions 70 at both corners of the front end portion 56a on the side in sliding contact with the end plate 10a. The fillet portion 70 is formed to have a first convex arc surface 72 having a radius of curvature R <b> 1, and the first convex arc surface 72 is brought into sliding contact with the concave arc surface 64 of the root portion 62 by the turning motion of the movable scroll 10.
In addition, the fixed tip seal 56 is locked to the fixed spiral body 50 at a concave portion 68, that is, a portion on the inner side in the width direction of the fixed tip seal 56 than the fillet portion 70. Further, the width W2 between the outer peripheral surfaces 56c of the side portions 56b forming the recess 68 is at least larger than the width W1 of the fixed and movable spiral bodies 50, 52, and the fixed chip seal 56 is located on the side portion from the tip portion 56a. It has a divergent shape over 56b.

  FIG. 3 shows a cross-sectional view of the fixed spiral body 50 of FIG. 2 as viewed from the III-III direction. As is clear from this figure, the convex portion 66 of the fixed spiral body 50 is formed over the central end portion 54 of the fixed spiral body 50, and the fixed chip seal 56 is a bag shape covering the entire central end portion 54 of the solid spiral body 50. The central end 74 is formed with a second convex arc surface 76 having a radius of curvature R2 in the vicinity of the tip.

The curvature radius R0 of the concave arc surface 64, the curvature radius R1 of the first convex arc surface 72, and the curvature radius R2 of the second convex arc surface 76 satisfy the following relationship.
R2> R1
(R0−0.1mm) ≦ R1 ≦ (R0 + 0.1mm)
If the above equation holds, it is possible to realize a smooth swiveling motion of the movable spiral body 52 while ensuring the seal between the fillet portion 70 and the root portion 62 in consideration of the moldability of the fixed tip seal 56. is there.

  As described above, in the compressor 1 of the first embodiment, the tip seal 56 has the fillet portion 70 including the first convex arc surface 72 at the corner of the tip end portion 56a. It is possible to suppress the stress concentration that has occurred at the corner of the tip of 52. Further, since the first convex arc surface 72 of the tip end portion 56a is in sliding contact with the concave arc surface 64 of the root portion 62, the airtightness of the refrigerant compression chamber 60 formed between the spiral bodies 50 and 52 is improved, The size of the compressor 1 can be reduced while improving the compression efficiency.

Further, since the concave portion 68 is provided on the inner side in the width direction of the chip seal 56 than the fillet portion 70, slight deformation of the fillet portion 70 is allowed with the sliding contact of the fillet portion 70 with respect to the root portion 62. When the fillet portion 70 is pressed, the fillet portion 70 is deformed to fill a minute crescent-shaped gap between the fillet portion 70 and the root portion 62, thereby sealing between the spiral bodies 50 and 52, and thus the compression chamber. The airtightness of 60 can be further increased.
Further, when the radius of curvature of the first convex arc surface 72 is R1 and the radius of curvature of the second convex arc surface 76 is R2, the relationship represented by R2> R1 is satisfied. It is possible to form a continuous and smoothly curved surface at the central end portion 54, and the sealing performance between the spiral bodies 50 and 52, and thus the airtightness of the compression chamber 60 can be further enhanced.

  Furthermore, when the radius of curvature of the concave arc surface 64 is R0 and the radius of curvature of the first convex arc surface 72 is R1, the relationship represented by (R0−0.1 mm) ≦ R1 ≦ (R0 + 0.1 mm) is satisfied. Therefore, the radius of curvature of the concave arc surface 64 and the first convex arc surface 72 can be set within an appropriate range taking into account the elastic deformation of the tip seal 56, and the sealing performance between the spiral bodies 50 and 52, and consequently the compression chamber 60, can be set. The airtightness can be further improved.

4 to 6 show details of the shapes of the root portion 62 of the movable spiral body 52, the fixed tip seal 56, and the distal end portion 50a of the fixed spiral body 50 according to the second embodiment, respectively. FIG. 9 shows a state in which the movable scroll 10 according to the second embodiment is assembled, and FIG. 9 shows a state in which the movable scroll 10 according to the second embodiment is turned.
As is apparent from FIGS. 4 to 6, the movable spiral body 52 has the root portion 62 standing from the end plate 10 a with an angle θ 1 (usually θ 1 = 90 °), and the fixed tip seal 56 forms a recess 68. The angle between the outer peripheral surface 56c of the side portion 56b and the distal end surface 56d of the distal end portion 56a, that is, the angle representing the degree of expansion of the fixed tip seal 56 is formed at an angle θ2.

Further, the fixed spiral body 50 is formed with a stepped portion 78 having a width W3 from the convex portion 66 on both sides of the convex portion 66 at the tip portion 50a, while the fixed tip seal 56 has a side portion thereof. 56b is formed having a width of W4.
Furthermore, as described above, the fixed spiral body 50 has a width W1 in the width direction, and the fixed chip seal 56 is formed with a width W2 between the outer peripheral surfaces 56c of the side portions 56b. The fixed chip seal 56 is formed such that the tip end portion 56a has a thickness T1 in the height direction and the side portion 56b has a thickness T2 in the height direction.

The angle θ1 of the root portion 62, the end spread angle θ2 of the fixed tip seal 56, the width W1 of the fixed spiral body 50, the width W2 between the outer peripheral surfaces 56c, the width W3 of the stepped portion 78, the width W4 of the side portion 56b, and the tip The thickness T1 of the part 56a and the thickness T2 of the side part 56b satisfy the following relationship.
W2> W1
(W3-W4) <0.2mm
θ1 <θ2
T2> R1 (R1: radius of curvature of the first convex circular arc surface 72)
T1> 1mm

If the above equation holds, it is possible to realize a smooth swiveling motion of the movable spiral body 52 while ensuring the seal between the fillet portion 70 and the root portion 62 in consideration of the moldability of the fixed tip seal 56. is there.
Specifically, as shown in FIG. 7, when the movable part 10 is assembled to the fixed scroll 8 and the root part 62 and the fillet part 70 face each other at a distance from each other, the fixed tip seal 56 has an angle θ <b> 2. Because of the shape, a wedge-shaped gap G is formed between the side portion 56 b opposite to the side surface 80 side of the movable spiral body 52 and the convex portion 66.

Next, as shown in FIG. 8, when the side surface 80 of the movable spiral body 52 is brought into contact with the side surface 82 of the fixed spiral body 50 when the movable scroll 10 is assembled to the fixed scroll 8, the fixed chip seal on the side surface 80 side. The side portion 56b of 56 is pressed against the side surface 82, and the side portion 56b on the side opposite to the side portion 56b on the side surface 80 side is further inclined so that the gap G is further increased.
Next, as shown in FIG. 9, when the end plate 10 a of the movable scroll 10 is pressed against the tip surface 56 d of the fixed chip seal 56 and the fixed and movable spiral bodies 50 and 52 are completely engaged with each other, the gap G is substantially reduced. It is completely crushed, and the seal between the fillet portion 70 and the root portion 62 is assisted by the elastic force of the fixed tip seal 56 itself.

  As described above, in the compressor 1 of the second embodiment, the relational expressions of the dimensions and shapes of the root portion 62, the fixed tip seal 56, and the fixed spiral body 50 described above are established. When the width of the seal 56 is W2, the relationship represented by W2> W1 is satisfied, so that the tip surface 56d of the spiral body 50 can be reliably protected by the tip seal 56 and the fillet with respect to the root portion 62 is achieved. The part 70 can be reliably pressed, and the sealing performance between the spiral bodies 50 and 52 and the airtightness of the compression chamber 60 can be further enhanced.

10 shows details of the shape of the fixed tip seal 56 according to the third embodiment, FIG. 11 shows the movable scroll 10 according to the third embodiment during a turning motion, and FIG. 12 shows the fixed spiral body 50 of FIG. Is a cross-sectional view seen from the XII-XII direction.
As shown in FIG. 10, in this embodiment, the auxiliary rib 86 that assists the seal between the first convex arc surface 72 and the concave arc surface 64 of the root portion 62 with the third convex arc surface 84 is a fillet portion. 70 and a single unit. The auxiliary rib 86 has a lower abrasion resistance than at least the end plate 10 a of the movable scroll 10, preferably higher in abrasion resistance than the fixed chip seal 56, and at least equal to or more than the elastic coefficient of the fixed chip seal 56. It is shape | molded from the material which has this.

The curvature radius R3 of the third convex arc surface 84 described above satisfies the following relationship.
R3 ≦ R0 ≦ R1 (R0: radius of curvature of concave arc surface 64, R1: radius of curvature of first convex arc surface 72)
If the above equation holds, it is possible to realize a smooth swiveling motion of the movable spiral body 52 while ensuring the seal between the fillet portion 70 and the root portion 62 in consideration of the moldability of the fixed tip seal 56. is there.

  Specifically, as shown in FIG. 11, during the orbiting movement of the movable scroll 10, the auxiliary rib 86 is formed from the material having the above-described wear resistance and elastic coefficient, and the above-described third convex arc surface 84. Therefore, the third convex arc surface 84 is worn in a complementary shape of the concave arc surface 64 of the root portion 62 as it slides on the root portion 62. As a result, a fourth convex circular arc surface 88 having a radius of curvature R4 substantially equal to R0 is formed, and the elastic force of the fixed tip seal 56 itself is combined to further ensure the seal between the fillet portion 70 and the root portion 62. Assisted by.

Further, as shown in FIG. 12, the auxiliary rib 86 is formed such that the length of the fixed spiral body 50 in the spiral direction gradually decreases as it approaches the central end portion 54, and the auxiliary rib 86 becomes denser as it approaches the central end portion 54. It is preferable to arrange them sequentially.
As described above, in the compressor 1 of the third embodiment, the auxiliary rib 86 is provided on the first convex arc surface 72 of the fillet portion 70, the radius of curvature of the concave arc surface 64 is R 0, and the first convex arc surface 72. Is a fourth convex arc surface having a radius of curvature R4 substantially equal to R0, where R3 ≦ R0 ≦ R1 is satisfied, where R1 is the radius of curvature of R3 and the radius of curvature of the third convex arc surface 84 is R3. 88 is formed, it is possible to set the curvature radii of the concave arc surface 64 and the first convex arc surface 72 within a range in which the wear of the auxiliary rib 86 is taken into account, and the sealing performance between the spiral bodies 50 and 52, and thus the compression chamber. The airtightness of 60 can be further increased.

Specifically, when the fillet portion 70 is pressed against the root portion 62, the wedge-shaped oil film formed in the region where the compression chamber 60 is formed cooperates with the auxiliary rib 86, whereby the refrigerant The leakage path can be completely blocked, and the sealing performance between the spiral bodies 50 and 52 and the airtightness of the compression chamber 60 can be effectively enhanced.
In addition, since the refrigerant leakage path can be completely blocked, it is possible to prevent the backflow of the refrigerant, the refrigerant pressure drop, and the noise accompanying the fluctuation of the movable scroll caused by these.

  In addition, since the plurality of auxiliary ribs 86 are densely provided closer to the central end portion 54 of the spiral body 50, the wear of the auxiliary ribs 86 is taken into account in the vicinity of the central end portion 54 where the pressure in the compression chamber 60 becomes the highest. Within this range, the radius of curvature of the concave arc surface 64 and the first convex arc surface 72 can be set, and the sealing performance between the spiral bodies 50 and 52 and thus the airtightness of the compression chamber 60 can be further enhanced.

The present invention is not limited to the above-described embodiment, and various modifications can be made.
For example, the shape of the chip seal 56 of the present invention is not necessarily limited to a concave cross section, and for example, a convex portion (locking portion) 92 of a chip seal 90 formed in a convex cross section as shown in FIG. You may mount in the formed recessed part 94. FIG.
Further, the tip seal 56 and the auxiliary rib 86 of the present invention are not necessarily provided over the entire circumference of the spiral bodies 50 and 52. For example, as shown in FIGS. It may be provided only in the range of one spiral from the central end portion of the movable spiral body 52. In this case, the sealing of the compression chamber 60 that is high pressure near the central end portion of the movable spiral body 52 is effective at low cost. It is preferable that it can assist.

Further, in this case, the outer end portion 96 of the movable tip seal 58 is shaped so that the end surface thereof is along the turning direction of the movable scroll 10 (the arrow direction in FIG. The outer end 96 is pressed against the tip 50a of the fixed spiral body 50 by the pressure of the compression chamber 60 formed on the portion side, which is preferable because the compression chamber 60 can be reliably sealed.
Furthermore, in the present invention, the fillet portion 70 and the auxiliary rib 86 may be provided on the tip seal of the scroll body of at least one of the fixed and movable scrolls 8 and 10, and these portions are not necessarily fixed and movable chips. It is not necessary to provide both the seals 56 and 58 or both the fixed and movable spiral bodies 50 and 52.

  Finally, it goes without saying that the present invention can be applied not only to a scroll compressor but also to scroll-type fluid machines in general such as a scroll expander in which an expansion chamber is defined as a refrigerant pressure chamber.

1 Scroll compressor (scroll type fluid machine)
8 Fixed scroll 8a End plate 10 Movable scroll 10a End plate 50 Fixed spiral body (spiral body)
52 Movable spiral body (spiral body)
54 Center end 56 Fixed chip seal (chip seal)
56a Tip 58 Movable tip seal (tip seal)
60 Compression chamber (pressure chamber)
62 Root part 64 Concave arc surface 68 Concave part (locking part)
70 Fillet portion 72 First convex arc surface 76 Second convex arc surface 84 Third convex arc surface 86 Auxiliary rib 90 Fixed chip seal (chip seal)
92 Convex (locking part)

Claims (7)

Each includes an end plate and a fixed scroll and a movable scroll having a spiral body integral with the end plate, and the spiral body and the end plate are interposed between the fixed and movable scroll via a chip seal provided on the spiral body. A scroll type fluid machine that partitions a pressure chamber of a working fluid formed between the spiral bodies by sliding contact with each other,
The scroll body of at least one scroll has a root portion made of a concave arc surface at a corner on the end plate side, and the tip seal of the other scroll is in sliding contact with the concave arc surface at the corner of the tip end portion. A scroll type fluid machine having a fillet portion comprising one convex arc surface.   2. The scroll according to claim 1, wherein the tip seal includes a locking portion that is locked to the spiral body, and the locking portion is provided on an inner side in the width direction of the tip seal than the fillet portion. Type fluid machine. The width of the spiral body is W1,
When the tip seal width is W2,
W2> W1
The scroll type fluid machine according to claim 1, wherein the relationship indicated by The tip seal has a second convex arc surface covering the center end of the spiral body,
The radius of curvature of the first convex arc surface is R1,
When the curvature radius of the second convex arc surface is R2,
R2> R1
The scroll type fluid machine according to claim 1, wherein the relationship indicated by The radius of curvature of the concave arc surface is R0,
When the radius of curvature of the first convex arc surface is R1,
(R0−0.1mm) ≦ R1 ≦ (R0 + 0.1mm)
The scroll type fluid machine according to claim 1, wherein the relationship indicated by The first convex arc surface of the fillet part is provided with an auxiliary rib for assisting the seal with the concave arc surface with the third convex arc surface,
The radius of curvature of the concave arc surface is R0,
The radius of curvature of the first convex arc surface is R1,
When the radius of curvature of the third convex arc surface is R3,
R3 ≦ R0 ≦ R1
The scroll type fluid machine according to claim 1, wherein the relationship indicated by   The scroll type fluid machine according to claim 6, wherein the plurality of auxiliary ribs are densely provided closer to a central end of the spiral body.

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